如何防止"aspxerrorpath"作为查询字符串传递给ASP.NET自定义错误页面

 <customErrors mode="Off" />
</system.web>

Sub Application_Error(ByVal sender As Object, ByVal e As EventArgs)
    Dim ex As Exception = Server.GetLastError()
    Dim httpEx As HttpException = TryCast(ex, HttpException)
    If httpEx IsNot Nothing Then
        Dim errorCode As Integer = httpEx.GetHttpCode()
        If errorCode >= 400 And errorCode < 600 Then
            Server.ClearError()
            Response.Redirect(String.Format("/Error.aspx?code={0}", errorCode))
        End If
    End If
End Sub

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
    Dim errorCode As Integer = Request.QueryString("code")
    If errorCode >= 400 And errorCode < 600 Then
        lblErrorMessage.Text = String.Format("An error occurred. Error code: {0}", errorCode)
    Else
        lblErrorMessage.Text = "An unknown error occurred."
    End If
End Sub

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
    Dim errorCode As Integer = Request.QueryString("code")
    If errorCode >= 400 And errorCode < 600 Then
        lblErrorMessage.Text = String.Format("An error occurred. Error code: {0}", errorCode)
        Dim errorPath As String = Request.QueryString("aspxerrorpath")
        If Not String.IsNullOrEmpty(errorPath) Then
            Response.Redirect(String.Format("/Error.aspx?code={0}", errorCode))
        End If
    Else
        lblErrorMessage.Text = "An unknown error occurred."
    End If
End Sub